Answer:
1- Carbon dioxide in our breath comes from the carbon in our food.
2- All plants need carbon dioxide to survive.
3- About .04 percent of the atmosphere's air is carbon dioxide and 4.4 percent of our breath is carbon dioxide we breathe out more carbon dioxide than we breathe in.
4- Some effects might include combustion with other gasses and it could also potentially kill all life.
Step-by-step explanation: